1. Field of the Invention
The present invention generally relates to a video game device, and particularly relates to a game device capable of expressing more realistic images in game devices installed at an amusement center or home and an image processing device used in such game device.
2. Description of the Related Art
Pursuant to the development of computer technology, video game devices using computer graphics technology have come into general use. Video game devices of this kind are widely accepted by the users. A number of game devices of various kinds has been devised, and a variety of game software corresponding to such devices is being supplied.
In order for users to further enjoy video games, it is desirable that images with more realistic expressions are displayed on a screen. In vehicle races such as a car race, for example, it is desirable that the movement of vehicles or background is expressed naturally.
As one of the elements to express this natural movement, a data reading control may be proposed in which data of a vast game space is read from a recording medium such as a CD-ROM into the memory inside the game device and thereafter displayed.
Although the same game space, in the case of a game space for games in which characters move slowly as in an RPG (Role Playing Game) or a movement of a character to another location is made in an instant, the data may be read upon temporarily suspending the image processing. Accordingly, such data reading control is very easy.
However, in case of games in which consecutive movement of characters gives a great deal of influence to the nature of the game, as in a car race game, etc., background data required to be read together with the movement of the vehicle amount to a huge volume. Accordingly, such data reading control becomes very complicated. For example, if data reading is executed upon temporarily suspending image processing as in the case of RPG, the game will stop and would not be effective in a car race game. Reading into a memory all of the background data of the vast game space from a CD-ROM, etc. is practically impossible from the perspective of memory space and time required for reading.
Accordingly, in case of games which express scenes with characters moving at high speed as in conventional car race games, image processing was executed by dividing background data along travelling route per area, and pre-reading background data for required areas.
However, a game compatible with this pre-reading method is, for example, a car race game in which a vehicle as a moving object runs a predetermined course (travelling route). A method for this case was simple, in which background data of the following area was to be memorized in the available memory space upon the vehicle passing a certain point on the course. Some recent car race games or car games enable a player to drive the vehicles in any direction within the game space. In this kind of game, the travelling directions of a vehicle, which include a plurality of branching running route or areas such as a prairie that is not a part of the original running route, are subject to the player's operation. In other words, it becomes very difficult for the device to simply figure out the running route block on which the car may run in the near future and pre-read background data based on the current speed or location of the vehicle.
Accordingly, the object of the present invention is to provide smooth, stable and high quality game images by accurately pre-reading background data required for image processing each time, with a simple method, in games in which a player can move an object such as a vehicle to arbitrary directions within the game space.